/Engine/Source/Runtime/Core/Public/ProfilingDebugging/CookStats.h
Every stat is essentially a name followed by an array of key/value "attributes" associated with the stat.
typedef [TKeyValuePair](API\Runtime\Core\ProfilingDebugging\FCookStatsManager\TKeyValuePair)< [FString](API\Runtime\Core\Containers\FString), [FString](API\Runtime\Core\Containers\FString) > StringKeyValue